.middle > div:nth-child(1) {
    height: 50px;

}

.middle > div:nth-child(1) > div {
    border-bottom: 1px dashed gray;
}

.course-nav > div:hover .quan {
    visibility: visible;
}

.course-nav > div:hover {
    color: rgb(243, 101, 37);
    cursor: pointer;
}

.online .chinese-name {
    font-size: 50px;
    color: rgb(243, 101, 37);
    margin: 20px;
}

.online .english-name {
    font-size: 30px;
    margin: 20px;
}

/*---------------预约-----------------*/

.online > div:nth-child(2) > div:nth-child(1) {
    /*border: 1px solid gray;*/
    width: 300px;
    margin: 50px;
    text-align: center;
}

.online > div:nth-child(2) > div:nth-child(1) > div > div:nth-child(1) {
    font-size: 50px;
    color: gray;
}

.online > div:nth-child(2) > div:nth-child(1) > div img {
    width: 200px;
    height: 150px;
    margin: 30px 0;
}

.online > div:nth-child(2) > div:nth-child(2) {
    border: 1px solid gray;
    width: 500px;
}

/*------------------表单-----------------*/
form > div > div {
    margin: 10px 0;
}

form > div > div > div:nth-child(1) {
    line-height: 30px;
    font-size: 20px;
}

/*逗号分组选择器*/
input, textarea {
    width: 400px;
    border: 1px solid gray;
    height: 30px;
    line-height: 30px;
    padding: 0 10px;
}

textarea {
    height: 100px;
    resize: vertical;
    max-height: 200px;
}

/*属性选择器*/
input[type=submit] {
    width: 422px;
    background-color: rgb(243, 101, 37);
    color: white;
}